21602765813579 has 2 divisors, whose sum is σ = 21602765813580. Its totient is φ = 21602765813578.

The previous prime is 21602765813533. The next prime is 21602765813597. The reversal of 21602765813579 is 97531856720612.

Together with next prime (21602765813597) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21602765813579 is a prime.

It is not a weakly prime, because it can be changed into another prime (21602765803579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10801382906789 + 10801382906790.

It is an arithmetic number, because the mean of its divisors is an integer number (10801382906790).

Almost surely, 2^{21602765813579} is an apocalyptic number.

21602765813579 is a deficient number, since it is larger than the sum of its proper divisors (1).

21602765813579 is an equidigital number, since it uses as much as digits as its factorization.

21602765813579 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38102400, while the sum is 62.

The spelling of 21602765813579 in words is "twenty-one trillion, six hundred two billion, seven hundred sixty-five million, eight hundred thirteen thousand, five hundred seventy-nine".